Research is designed to yield new insights into basic mechanisms and interrelationships of homologous chromosome pairing, recombination, crossover interference and maintenance of chiasmate association until anaphase I distribution. These processes are fundamental to the basic mechanisms of inheritance, and especially so to the production of normal gametes, such that each will have a complete chromosome set, without extra chromosomes, and aneuploid abnormalities in the offspring are avoided. Approaches combine application of new techniques and laboratory findings to experimental material with an appropriate repertoire of meiotic and morphological chromosome variants.